• 제목/요약/키워드: Link Quality

검색결과 763건 처리시간 0.027초

Wireless Communication Quality Improvement Through DSES Alarmed Noise Image Restoration

  • Ki-Hwan, Kim;HyunHo, Kim;HoonJae, Lee
    • 한국컴퓨터정보학회논문지
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    • 제28권2호
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    • pp.55-62
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    • 2023
  • 우주에서 지상 기지국까지 무선 데이터 전송을 성공하기 위해서는 전파가 불안정한 대기권을 통과해야만 한다. 국제 우주 데이터 시스템 자문 위원회(CCSDS)가 요구하는 Data link 알고리즘은 암호화와 수신측 오류를 감지하고 재동기가 가능해야한다. 그러나 오류 복원은 CCSDS 요구조건에 포함되지 않는다. 본 논문에서는 다양한 잡음에 내성과 오류 복원이 가능한 알고리즘을 제안한다. 잡음 제거 필터와 선명도를 향상시키는 필터 그리고 EDSR 등을 통해 가우시안, Salt, Pepper, S&P 잡음 등 다양한 환경을 고려하여 실험하였으며, 그 결과 잡음 억제와 보정에 도움이 된 것을 확인하였다. 추가적으로 유사 알고리즘인 SES Alarmed와 DSES Alarmed와 비교한다.

An ANN-based Intelligent Spectrum Sensing Algorithm for Space-based Satellite Networks

  • Xiujian Yang;Lina Wang
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제17권3호
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    • pp.980-998
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    • 2023
  • In Low Earth Orbit (LEO) satellite networks, satellites operate fast and the inter-satellite link change period is short. In order to sense the spectrum state in LEO satellite networks in real-time, a space-based satellite network intelligent spectrum sensing algorithm based on artificial neural network (ANN) is proposed, while Geosynchronous Earth Orbit (GEO) satellites are introduced to make fast and effective judgments on the spectrum state of LEO satellites by using their stronger arithmetic power. Firstly, the visibility constraints between LEO satellites and GEO satellites are analyzed to derive the inter-satellite link building matrix and complete the inter-satellite link situational awareness. Secondly, an ANN-based energy detection (ANN-ED) algorithm is proposed based on the traditional energy detection algorithm and artificial neural network. The ANN module is used to determine the spectrum state and optimize the traditional energy detection algorithm. GEO satellites are used to fuse the information sensed by LEO satellites and then give the spectrum decision, thereby realizing the inter-satellite spectrum state sensing. Finally, the sensing quality is evaluated by the analysis of sensing delay and sensing energy consumption. The simulation results show that our proposed algorithm has lower complexity, the sensing delay and sensing energy consumption compared with the traditional energy detection method.

주의력결핍/과잉행동장애 아동 가족의 삶의 질 영향 요인 (Factors Influencing Family Quality of Life among Mothers of Children with ADHD)

  • 오원옥
    • Child Health Nursing Research
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    • 제14권4호
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    • pp.396-404
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    • 2008
  • Purpose: This study was conducted to identify the level of quality of family life, parental locus of control, and parental sense of competence, and to elucidate factors that influence family quality of life in the mothers of children with Attention Deficit/Hyperactive Disorder (ADHD). Method: A convenient sample of mothers from 6 child psychiatric clinics was used in this cross-sectional survey design. Questionnaires used for data collection included the following scales: Family Quality of Life, Parental Locus of Control-Short Form Revised, Parental Sense of Competence. Results: The level of family quality of life was mid-range. A positive relationship was found between Family Quality of Life and the research variables. The significant predictors of family quality of life were parental locus of control, parental sense of competence, and duration of medication and these variables accounted for 21.8% of the variance in family quality of life. Conclusions: These results indicate that family quality of life is an important factor which health care provider should assess and evaluate for children with ADHD and their families. The results of this study suggest that family quality of life is an important link with parental sense of competence and parental locus of control.

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CDMA2000 1x 역방향 링크의 신호 품질 측정 알고리즘 (A Signal Quality Measurement Algorithm for CDMA2000 1x Reverse-link)

  • 강성진
    • 한국항행학회논문지
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    • 제16권6호
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    • pp.997-1004
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    • 2012
  • 본 논문에서는 CDMA2000 1x 단말기 신호의 품질 측정을 위한 알고리즘을 제안하고 구현하였다. 제안된 알고리즘은 PC 기반 플랫폼에서 소프트웨어로 구현이 가능하도록 하였으며, 4배 오버샘플링된 입력 신호에 대하여 등화, PN 부호 동기 및 추적, 주파수 및 위상 오프셋 보상을 수행하여 수신 신호가 추출되고, 추출된 신호로부터 역확산, 복조를 통해 측정에 사용될 기준 신호를 재생성한다. 이 재생성된 신호와 추출된 신호를 이용하여 단말기의 신호 품질을 측정한다.

The Impact of Food Quality on Experiential Value, Price Fairness, Water Park Image, Satisfaction, and Behavioral Intention in Context of Water Park

  • Lee, Sang-Mook
    • 한국조리학회지
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    • 제22권1호
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    • pp.87-95
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    • 2016
  • The purpose of current study is to develop and estimate a proposed model that explains the potential relationships among food quality, experiential value, price fairness, image, satisfaction, and behavioral intention in context of water park. In addition, the study will verify how these factors link to each other. Results show that food quality is a significant antecedent of experience value, price fairness, water park image. Also, the experiential value and water park image influence on visitors' satisfaction. Last, the satisfaction is critical predictor of behavioral intention. These findings will contribute to understand the consumers' perception about water park, and how derives the customer satisfaction and behavioral intention. In sum, present study will serve insights for industry marketers and managers in water park segment.

Nondestructive Techniques for Quality Inspection of Fruits and Vegetables

  • Young J. Han;Cho, Young-Jin;Wayne S. Rial;Wade E. Lambert
    • Preventive Nutrition and Food Science
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    • 제2권3호
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    • pp.269-279
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    • 1997
  • Various nondestructive technologies for quality inspection of fruits and vegetables were reviewed through published literatures and selected agricultural databases. These technologies were grouped into nine categories, including acoustic response, dielectric response, machine vision, magnetic response, mechanical vibration response, microwave response, optical properties, and other possible sensing technologies. Their principles and characteristics were investigated and these technologies were presented with their current and potential applications. The link of appropriate nondestructive technologies with common principal quality parameters of fruits and vegetables was summarized.

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Relay Station 시스템의 Throughput 향상을 위한 Auction 기반 계층적 링크 할당 알고리듬 (An Auction based Hierarchical Link Allocation Algorithm for Throughput Improvement of Relay Station Systems)

  • 강해린;유혜인;김낙명
    • 대한전자공학회논문지TC
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    • 제46권6호
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    • pp.11-18
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    • 2009
  • 본 논문에서는 relay station (RS)이 도입된 이등통신 시스템의 throughput 향상을 위해 base station (BS)와 RS 및 단말간의 link를 hierarchical하게 allocation하는 auction 기반의 알고리듬을 제안한다. Hierarchical link allocation 방식은 인지무선 기능을 가진 각 RS 단위로 일차적으로 해당 서비스 영역 내의 단말들을 대상으로 QoS 만족 여부를 감지하여 RS와 연결될 단말의 set을 정하고, BS 차원에서 해당 단말 set을 대상으로 auction 과정을 진행하여 최종적으로 BS 및 RS와의 link를 지정하는 방식이다. 제안하는 알고리듬에서는 시스템 throughput의 향상을 위해 인접 셀과의 정보 교환을 통해 얻은 co-channel interference (CCI) 정보 및 RS들로부터 수집한 단말 별 QoS의 개선량에 관한 정보를 바탕으로 auction 과정을 진행하며, auction winner 단말 set에 RS와의 link를 선별적으로 지정한다. 모의실험을 통하여 본 논문에서 제안하는 방식을 적용한 시스템은 셀 내 높은 QoS를 요구하는 사용자의 비율이 높아질수록 기존 알고리듬에 비해 단말의 QoS를 보다 효과적으로 만족 시킬 수 있음을 보였다. 또한 셀의 traffic load가 높고 인접 셀 CCI의 전력이 강할수록 기존의 알고리듬을 적용한 시스템보다 robust한 throughput 성능을 보였다.

SWMM과 WASP5 모형을 사용한 하구담수호의 수질 예측 (Prediction of water quality in estuarine reservoir using SWMM and WASP5)

  • 윤춘경;함종화
    • 한국환경농학회지
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    • 제19권3호
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    • pp.252-258
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    • 2000
  • SWMM and WASP5 were applied for pollutant loading estimate from watershed and reservoir water quality simulation, respectively, to predict estuarine reservoir water quality. Application of natural systems to improve estuarine reservoir water quality was reviewed, and its effect was predicted by WASP5. Study area was the Hwa-Ong reservoir in Hwasung-Gun, Kyonggi-Do. Procedures for estimation of pollutant loading from watershed and simulation of corresponding reservoir water quality were reviewed. In this study, SWMM was proved to be an appropriate watershed model to the nonurban area, and it could evaluate land use effects and many hydrological characteristics of catchment. WASP5 is a well known lake water quality model and its application to the estuarine reservoir was proved to be suitable. These models are both dynamic and the output of SWMM can be linked to the WASP5 with little effort, therefore, use of these models for reservoir water quality prediction in connection was appropriate. Further efforts to develop more logical and practical measures to predict reservoir water quality are necessary for proper management of estuarine reservoirs.

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The Effect of Prior Financial Performance on Organizational Reputation and Earnings Management

  • HUYNH, Quang Linh;NGUYEN, Nguyen Van
    • The Journal of Asian Finance, Economics and Business
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    • 제6권4호
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    • pp.75-81
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    • 2019
  • The paper aims to investigate the linkage among prior financial performance, organizational reputation and earnings quality. Firstly, it examines the influence of prior financial performance on organizational reputation and on earnings quality. Secondly, this research explores the moderating role that prior financial performance plays in the causal relationship from organizational reputation to earnings quality. Thirdly, the mediating role of organizational reputation in the effect of prior financial performance on earnings quality is analyzed. The empirical findings show that, prior financial performance positively affects both earnings quality and organizational reputation that in turn partly mediates the causal connection from prior financial performance to earnings quality; whereas prior financial performance imposes a positive moderation in the influence of organizational reputation on earnings quality. This research is expected to provide scholars and practitioners with a thorough understanding of the complex link among prior financial performance, organizational reputation and earnings quality. That helps them to deliver good decisions on the investment of suitable resources in maintaining and enhancing their organizational reputation, which assures a higher quality of reported earnings that in turn improves involved stakeholders' confidence in their firm. This likely leads the firms to gain better performance in the future.

150kVA급 전기품질 보상기기 제어 알고리즘 설계 (The Design of control algorithm for 150kVA power quality compensator)

  • 전진흥;김지원;전영환;김호용
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2001년도 하계학술대회 논문집 B
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    • pp.1070-1072
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    • 2001
  • In recent years, customers and power supplies are interested in power quality. Demands of customers are change from standard quality of distribution power system to various high quality of distribution power system. so, it is necessary to apply power quality compensator, in our project, we develop the power quality compensator of 150kVA which compensates power factor and voltage sag, interruption. it is very frequently occurred power qualify problems[1,2]. As a series and shunt compensator, power quality compensator consists of two inverters with common do link capacitor bank. It compensates the current quality in the shunt part and the voltage qualify in the series part. In this paper we present the design and control algorithm of power quality compensator. As a control algorithm is implemented by digital controller, we consider sample-and-hold of signals. In this simulation, we use EMTDC/PSCAD V3.0 software which can simulate instantaneous voltage and current.

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